Well survey system



Dec. 7, 1943. E. M. IRWIN ET A1.

WELL SURVEY SYSTEM Filed Oct. 4, 1958 4 Sheets-Sheet l Dec. 7, 1943. E.M. IRWIN ET AL 2,336,101

WELL SURVEY SYSTEM Filed oct. 4, 1938 4 sheets-sheet 2 7 1943 E. M. IRWIN ET AL 2,336,101-

WELL SURVEY SYSTEM Filed Oct. 4, 1938 4 Sheets-Sheet 3 AT RNE Dec. 7; 1943- E. M. IRWIN: E'rAL WELL SURVEY SYSTEM Filed Oct. 4, 1938 4 Sheets-Sheet 4 ATTRN.

Patented Dec. 7, 1943 WELL SURVEY SYSTEM Emmett M. Irwin, Pasadena, George E. Lewis, Al-

hambra, Richard H. Duval and Bruce H. Rule, Pasadena, and Ray M. Chenoweth, West Los Angeles, Calif., assignors to Cooperative Development Co., Los Angeles, Calif., a corporation of California Application October 4, 1938, Serial No. 233,208

(Cl. Z55- 1) 12 Claims.

Our invention relates to systems for making surveys or other measurements in oil wells and has particular reference to systems for convertlng measurements taken at great distances below the ground surface into signals which may be transmitted to the ground surface and there translated substantially simultaneously with the making of the measurement.

In the oil well industry it is frequently necessary to obtain information relative to the various conditions existing in the well at great distances below the ground surface. One such condition is that of determining whether or not a well bore in the process of drilling is following the true vertical line and, if not following such line, at what angle the bore is deviating therefrom from the true vertical. Another such condition is that during the drilling of the well, it is frequently necessary to not only determine the angle of deviation of well bores from the true vertical, but also to determine the compass direction in which such bore is deviated. It is also frequently/desired to survey the course which has been taken by a well bore, either at some point during the drilling thereof or after the drilling has been completed.

The instruments which are at present employed for obtaining such information may be roughly classifiedin two classes:

l) Those in which the determinations made by the instrument are recorded within the instrument itself requiring the instrument to be removed to the ground surface before the desired information is received; and

(2) 'I'hose in which theinformation is transmitted to the ground surface over an electrical signalling circuit extended from the ground surface through the well bore and to the instrument.

Both of these'classes of instruments embody numerous disadvantages and it has been long recognized that great savings in time and money could be effected were it possible to overcome these disadvantages.

Ina copending application, Serial No. 162,792. filed September 7, 1937, by Emmett M. Irwin, Ray M. Chenoweth and Richard H. Duval, there is disclosed a means for overcoming these disadvantages by transmitting signals to the ground surface as sound signals which are conveyed by the metal drill string used to rotate the drill bit.

The present invention is directed to a similar device and is directed particularly to a signal transmitting system which employs the column of mud or drilling fluid contained within the interior of the drill string as a transmission medium, thus avoiding the high transmission losses encountered when an attempt is made to transmit signals through the metal of the drill string.

It is, therefore,v an object of our invention to provide a sound transmission system by which a relatively weak signal produced within the well may be readily transmitted to the ground surface with a sufficiently small loss in amplitude to permit reception andvrecording of the same at the ground surface.

Another object of our invention is to provide a system for transmitting signals produced in an instrument located in a well to the column of fluid existing in `vthe well and for receiving such signal direct from the column of fluid at the ground surface, whereby the eiiiciency of the liquid column asia sound transmission medium may be readily employed. l

Another objectof our invention is to provide an instrument for making measurements at any desired location within an oil well and which may be exposed to ythe mud stream or other liquid,-

circulating in the well without substantial injury to the instrument.

Another object cf our invention is to provide an' instrument of the character set forth in the preceding paragraph wherein the instrument may be permanently located upon a drill string or other string of tubing extending into the well directly in the mud stream circulating through the well Without interference with the free circulation of mud or other drilling fluid in the well and with little or no injury to the instrument byV rality :of instrumentalities are employed andv adapted to measure a different condition or different angle of deviation of the instrument from the vertical with an improved relay device by which each of the individual measuring instrumentalities may be brought into play in a predetermined sequence in a time cycle.

Another object of our invention is to provide a measuring device which may be lowered into or disposed in an oil well, the instrument being self-contained and in which means controllable from the. ground surface are provided for selectively rendering the instrument active or inactive.

Another object of our invention is to provide an instrument of the charactersetforth in the preceding paragraphs with a control means which will set the instrument in operative condition and in which a well bore I is illustrated as being in the process of drilling by means of a drill bit 2, coupled through an instrument mounting device 43 to a drill collar 3, which is in turn connected at the lower end of a drill string 4 made up in `the. usual manner of -a .plurality ofl sections or lengths f drill pipe-extendingl upwardly to the with means for disconnecting motive power from .1'

the instrument at the expiration of, a predeter-` mined time after the instrument has been rendered operative.

Another object of our invention is to providean instrument of the character setl forth in the preceding paragraphs with'acontrolA switch of y extremely rugged construction adapted to con:`

trol the electric circuits and which will not be subject to destruction under the abuse which would be encountered in the normal handling of the instrument in the well.

Other objects of our invention. will be apparent froma study o f the following speciflcation read in connection with the accompanying drawings wherein:

Fig. 1 is a diagrammatic view ci an ou weil borne in the course ofA a d1illing operation and illustrating our 'invention as embodied in a device for measuring the angle of deviation of the well bore from the vertical.

Fig. 2 is a. cut-away View of one form of instrument for measuring the. angle of inclination of .fthe well bore from-the vertical and `embodying the` features of our invention. y

Fig. 3 is a detailed vertical sectionalview of one form of mounting device which may be interposed in a drill string or tubing string to mount I 'andv locate our instrument at a predetermined point in the well bore. i

Fig. 4 is a horizontal sectional view of the mounting device shown-in Figure, the section being taken along line IV-IV of Figure 3.,

Fig. 5 is. an enlarged vertical sectional view of .the signal producing and transmitting device constituting a part of the instrument shown in Fig. 6 isan enlarged viewv of the goose` neck ground surface 5, where the drill string is coupled by means of a kelly 6 to a rotary table 1 driven or rotated by means of any suitable power apparatus 8. Drill string 4 is supported upon a swivel 94 which is in turn suspended from a traveling block I0 of a-block and tackle assembly of which the stationary or crown block II is supported upon the upper end of a derrick structure or 4'tower I2.

' As is the usual practice of oil well drilling, the swivel 9 ,constitutes a means by which mud :duid or drilling fluid may be circulated down through the drill string 4 and upwardly about the drill string4, to carry away the cuttings, the mud fluid being pumped into the drill string 4 by means of any suitable well known pumping vvapparatus supplying this uid through a mud extending along the true vertical but will instead extend at a considerable angle to the vertical.

: The primary difllculty heretofore encountered in maintaining the vwellbore along a true vertical line or axis has 'been that the information to the effect that the well bore rhas deviated 1 from the vertical is not available to the driller or operator of the well until vafter such deviation has continued for a considerable depth of crooked connection or mud hose connection which may be employed atthe ground surface and showing the manner'in` whichthe signal .-pick-upadevice embodying` the principles of our invention may be attached thereto. y

Fig. 7 is an enlarged vertical sectional-view of a signalreceiver or pick-up device shown inFigure` 6. 1 y

Fig. 8 is a diagrammatic view of one form of electric wiring arrangement which may be employed to interconnect angle `measuring devices and signa-l producing'devices constructed in accordarice `with our invention.

Fig. 9 is a detailed vertical sectional view taken through one form of vibration responsive switch which may be employed in the practice of our invention.` l

Fig. 10 is a horizontalsectional view of the vibration responsive switch shown in Figure 9, the section being taken along line X--X of Figure 9. l

Fig. l1 is a vertical sectional View takenA through one form of controlling relay which may; be employed in the practice of .our inventionv v Fig. 12 is an exploded perspective view` ofthe contact carrier and contacts constituting a part of the relay shown in Figure 11.

Referring to the drawings, we have illustrated a typical well drilling vinstallation in Figure 1.

hole it being frequently necessary to `plug back the-crooked portion of the hole and rebore the same in order to insure the return of the bore to the .true vertical alignment. This difliculty may be avoided by providing an instrument which may be permanently secured to the drill string and located reasonably close to the drilling bit and actuated, in response'to the cessation of actual drilling operation or to a short pause in the rota-g tion of the drill bit, to notify the driller whether or not the bit is then making a true vertical bore or has deviated from the vertical.

Such an instrument may be constructed along the lines illustrated inFigure 2. and may include asuitable case or housing I5 within which is located a plurality of angle measuring devices or units I6 each comprising a disc-like base member I'I (see also Fig. 8) having an upper surface I8 upon which a ball or other rolling .ball to be displaced from its normal or central position when the housing vI 5 is tilted away from the true vertical position by an amount exceeding the angularity of the surface I8.

The surface yI 8 is preferably conical so that the ball will normally rest at. the apex of the cone,

that is, centrally of the surface I8, so that when the .housing is tilted as above statedthe'ball will j roll from' the. center vand toward the outer edge of the'base I1 until it engages a Contact ring 2| disposedslightly' above the base member I1 and insulated therefrom.`

The construction of each of the angle measurving units I6 may be identical except for the angle or the pitch of the cone-like surface upon the base so that the ball employed in the. unit will move from itsnormal position to its contacting ring position when the housing I5 is tilted at a diierent angle from that at which the balls of the remaining units will respond. It will be understood that as many of such units I6 may be employed as desired and the pitch of the cones of each of these devices may be varied in such so as to be actuated by or in response to any of these units which have been so tilted as to move their associated balls to contact making position. As a means for consecutively connecting the angle measuring units I6 to the sounding device 22, we prefer to provide a plurality of relays 23 arranged in an electric circuit hereinafter more fully described. Each of the relays 23 is preferably constructed as illustrated in Figures l1 and l2 as small relay members or units having an external diameter adapting them to be readily received within the housing I5 and to be stacked one upon the other in a relatively small vertical space.

In addition to the relays 23 we provide switching apparatus which will automatically place lour instrument in operative condition when'the actual drilling operations are stopped or paused but which will normally hold the instrument in a non-operative condition during the actual rotation or drilling operations ofthe bit. We have illustrated one of suchswitching devices as a vibration responsive switch 24 arranged as illustrated particularly in Figures 9 and 10 to complete the circuit through its contacts whenever vibrations or motion of the switch ceases but f which will whenever shaken or vibrated move its contacts away from circuit closing position. If desired, a second vibration responsive switch 24A may be provided which will disconnect circuits established by the switch 24 at some predetermined time after these circuits have been established.

The housing l5 may also include a suitable source of electric current for operating the relays 23 and the sounding or signalling device 22, such source of current being illustrated in Figure 2 as comprising a plurality of small unit dry battery cells 25.

The instrumentalities contained within the housing I5 are so arranged that whenever the drill bit or drill string to which the instrument is attached comes to rest a sufficiently long period oi time to permit the vibration responsive switch 24 to close its contacts. power` will be supplied from the source of current or batteries 25 by which a signal impulse or vibration producing device, such as is indicated at 22, will be actuated a number of times within a given time cycle or period depending upon the number of angle measuring devices I6 which have been so tilted 1 away from the true vertical that their respective balls have been `moved into contact with the convtact ring 2l.

Ipositions. Whenever lthe signal producing device 'v 22 is actuated a pressure wave or series of sound or signal vibrations will be generated by the signalling device to b`e received at the ground sur- 42 into and through the mounting disc 39 face and there translated or recorded in terms of angle of deviation measurement.

The particular signallingV device 22 illustrated herein is especially adapted to produce signals or sound vibrations of a predetermined frequency to be transmitted directly to the mud stream or other column of liquid which may be contained within the well, so as to utilize the known high eiciency of transmission of sound or vibration signals through a body of water or other similar liquids. v

As shown in Figure 5, the sounding device 22 is preferably mounted at the upper end ofthe housing I5 and includes a diaphragm 26 constructed as a suitable disc of metal, the diameter of which ispreerably as large as can be securely supported within the open end 21 oi the housing I5.

The diaphragm disc V26 is preferably held in the end of the housing I5 by means of a cap ring 28 threaded as indicated at 29 upon the upper end of the housing I5 so as to press the diaphragm 26 into tight engagement with a mounting ring 3l) screwed into the interior of the upper end of housing I5, a suitable gasket 3I being interposed between the lower surface of the disc 26 and the mounting ring 30 to prevent the ingress of water, mud or other fluid into the interior of the housing.

Suspended from the mounting ring 30 is an By properly selecting the length and diameter v of the resilient rod 31 and the mass of the Weight 36, a blow by the solenoid core 34 upony the weight 36 will cause the diaphragm disc 26 to be vibrated at a predetermined frequency.

It is desirable that the weight of the core 34 be balanced by means of a spring 38, so that the initial pull by the coil 33 need be only sufficient to accelerate the core during its upward stroke thereof, the spring 38 being mounted below the coi] 33 by meansof a mounting disc 39 secured to and extending across the inner cage 32. AThe spring 38 has'one Vof its ends secured to a rod 40 which in turn is rigidly secured to the core 34 while the opposite end of spring 38 is secured to an adjusting sleeve 4I 'threaded as indicated at By suitably adjusting the sleeve 4I up and down toward the coil 33, length of stroke of the core 34 may be selected. rPhe coil 33 is adjustable vertically in the mounting cage as by means of screws 33a in elongated slots 33b to so position the coil that the dead center position of the core is with the hammer 35 just free of the weight 36. Thus the hammer 35 will strike only a single blow upon the Weight 36 for each energization of coil 33. Also the mass of the core 34 should be but slightly less than the mass of the weight 36 so that its rebound after impact will be sharply defined but of such low energy that it will be readily brought to rest by the effect of the energized coil.

It follows, therefore, that if the housing I5 is located upon the drill bit, drill collar r other portion of the drill string in such manner as to expose the diaphragm 26 to the mud fluid, circulation fluid. or other liquid column in the well, the signal vibrations resulting from an impact upon the weight 36 will be transmitted directly to the liquid column and thence upwardly to the ground surface.

While the housing I may be mounted in any suitable manner to expose the diaphragm 26 to the mud stream or liquid column, we prefer to employ a special mounting device illustrated particularly in Figs. 3 and-4 for the purpose of permitting direct contact between the diaphragm 26 and the liquid column without in any manner obstructing the circulation of mud or other drilling fluid through the drill string and also to avoid undue wear or abrasion upon the instrument by reason of the passage of the drilling fluid past the instrument. The mountin'device preferably includes the special sub 43 which may be mounted directly above the regular drill collar employed to mount the drill bit upon the string, such special sub being constructed of extra heavy large size drill pipe having an interior opening 44 somewhat in excess of the mud fluid or circulation opening in the regular drill pipe employed in the string.

The upper end of the sub 43 is provided with a coupling member 45, either constructed integrally with the sub 43 or as a part separate therefrom to provide a connection or coupling by which our special sub may be connected to the regular tool joints employed in the particular drill string with which it is to be associated. Similarly, the lower end of the sub 43 is provided with a coupling member 46 by which the special sub may be coupled with regular tool joints to the drill collar employed in the string.

Mounted within the enlarged opening 44 in our sub is an instrument carrier 41 which is preferably shaped as indicated in Fig. 4, having a cross section including at one side of the sub 43 an instrument tube 48 having an internal bore of a suitable size to receive the housing I5 containing the instrumentalities hereinbefore referred to. Extending from the instrument tube 48 are a pair of wings or webs 49 formed of a thin walled V-shaped section of metal the outer legs of the V shape joining each other at 5U and terminating in a counterweight 5I.

By referring particularly to Fig. 3 it will be observed that the instrument carrier 41 including the instrument tube 48, the wings 49 and the counterweight 5I, provides an elongated mount-- ing for the instrument housing I5 which will locate the instrument housing I5 at one side of the special sub while the sub will be balanced by the counterweight 5I in such manner as to permit relatively rapid rotation of the drill string Without undue vibration.

While the special sub 43 may be of any desired length, we prefer to construct the same of a length somewhat in excess of that which is required to accommodate the length of the instrube employed above the instrument carrier 41 to` provide an entirely unobstructed relatively large diameter passage for mud or other circulating fluids. Thus, mud fluids coming down through the regular drill string, will enter the sub 43 through a relatively restricted passage 53 in the tool joints and coupling member, at which time the mud fluid is travelling at a relatively high velocity. However, as the mud fluid enters the enlarged passage defined by the spacing sleeve 52 the velocity of the fluid will be materially reduced and any abrasive action upon the upper end of the instrument carrier 41 and particularly upon the upper end of the housing I5 which is exposed directly to the mud stream will be materially reduced. I

The diaphragm will vibrate against an upwardly directed column of liquid so that the greater portion of the energy in the diaphragm will be directed upwardly toward the ground surface.

By reason of the construction of the instrument carrier 41 a relatively large area of unobstructed passage is provided through the sub 43 for the mud fluid, as well as for other tools such as core barrel or other-devices commonly lowered through the drill string. The counterweight 5I may either be made solid or, if desired, may be provided with a longitudinally extending bore 5Ia to act as a housing for a portion or all of thel battery cells 25 employed in our instrument and thus the length of the housing I5, the sub 43 and carrier 41 may be materially reduced. The use of the counterweight 5| for this purpose also permits the employment of a large number of battery cells without requiring elongation of or increase in -length of the housing I5 or the sub used to mount it.

Also if desired the apices of the V shaped wings 49 may also be formed as tubular housing members for additional dry cell batteries if desired.

All of the instrumentalities contained within the housing I5 as well as the various dry cell batteries employed, either in the instrument housing or mounted separately in the instrument carrier 41, are separated from the cooling effects of the mud stream or circulating fluid by only relatively thin metal walls so that effective cooling of the instrument and batteries is accomplished by the continuous circulation of the circulating fiuid.

The signals of such predetermined frequency as the signalling device may be selected to produce, will as hereinbefore described be transmitted upwardly through the fluid column in the well to the ground surface where the same may be received and translated by suitable receiving apparatus which includes a sound or pressure wave responsive mechanism exposed to the effect of the pressure Waves sent up through the liquid column as by extending such mechanism into direct contact with the liquid column or sufficiently close thereto that the transmission qualities of the liquid column may be effectively utilized. This mechanism may be inserted into the bore to Contact the liquid column or as shown in Fig. 6 such signal receiving device may be mounted in a housing 55 which may be attached to or formed as an integral part of the usual goose neck 56 by which mud iiuid is pumped into the drill string at the ground surface (see Fig. 6).

As shown in Fig. 7, the housing 55 is provided at one of its ends with a cap 51, the central portion of which comprises a relatively heavy diaphragm 59 capable of responding to vibrations or sound signals imparted to it by the liquid column impinging upon the cap 51. A suitable lmicrophone 58 is illustrated as being mountedv within the housing 55 to receive and respond to vibrations ofthe diaphragm 59. While the microphone 58 may be of any desired character, we prefer to use a crystal type of microphone since it is peculiarly adapted to be secured to and form a part of a weight 58a which is in turn coupled to the diaphragm 59 by means of a resilient rod 60. By selecting the length and diameter of the rod 66 and the mass of the weight 58a (plus the mass of the microphone 58) the diaphragm 59 and the microphone 58 may be tuned to the same frequency to which the signal sending device 22 was tuned and thus the microphone 58 will respond only to vibrations of the selected or predetermined frequency and will not readily respond to other vibrations or sounds emanating from the well or from other apparatus employed in connection with the well such as mud pumps, hoisting equipment, etc.

For the purpose of assisting in the assembly and adjustment of the microphone58, weight 58a and rod 60, we prefer to mount the same upon a cylindrical inner frame 6l as by extending a. perforated diaphragm or spider v62 across the interior of the frame 6I, securing the outer edge of the diaphragm between clamping rings 63 and 64 secured in any suitable manner to the frame 8l and to secure the rod 60 through the center of the perforated diaphragm 62 as by means of adjustable lock nuts 65. Likewise, the weight 59 is mounted upon the upper end of the rod 60 by means of threading the end of the rod into a threaded bore 66 in the weight 58a and locking the same at any desired adjusted position by means of a lock nut 61. By providing suitable hand openings 68 in the frame 6I access may be had to the interior of the frame 6l to reach the lock nuts 65 and 61 for adjustment purposes.

The microphone 58 is illustrated as being coupled through a suitable amplifier 10 to a recorder 1l or to an audible translation device such as earphones 12, the circuit preferably passing through a band-pass filter indicated at 13 to assist further inlimiting response of the recorder 1l and earphones 12 only to the selected predetermined frequency emitted by the signal sending device 22.

The signalling device 22 and angle measuring devices I6 may be connected in a circuit such as that illustrated in Fig. 8 which is especially adapted to a relay construction of such a character 'as will permit its use under the tremendous vibrations, strains and abuse to which the instrument may be subjected during the drilling operation. Such relay structure is illustrated herein 6 in Figs. 11 and 12 as comprising a body member 14 which includes a disc-like portion 15 from the center of which extends a cylindrical stern 16 constituting the magnetic core of the relay. A coil 11 is mounted upon or wound upon the stem 16 and suitably insulated therefrom as by means of a tubular section 18 of insulating material stantially equal tothe thickness of the material from which the contact members 89a, 89b and frictionally secured to the stem 16 'd`havingg a\\ disc 19 of insulating material interposed between the upper endof the coil 11 and the innersurface of the disc portion of the housing 14. A second disc 86 of insulating material may be applied at the .lower end of the insulating tube 18. The stem 16 preferably extends slightly beyond thelower end of insulating tube 18 and has Theunderface surrounding its extreme lower end a spacer member or disc 8l preferably made of copper as will be more fully described hereinafter for the purpose of imparting time delay response oi the relay to energization of the coil 11.

A protective shell 82 constructed of magnetic material surrounds the coil 11, the upper end of the shell v82 abutting the body member 14 and being preferably received in a recessed portion 83 thereof. Shell 82 may be constructed of a length considerably in excess of the length of the core or stem 16' so that the lower end of the shell 82 may be employed as a housing and for mounting a'plurality of contact members to be actuated by the coil.

The movable contact piece or armature of the relay is illustratedfas comprising a metal ball 84 suspended in an ngated cylindrical bore 85 to move towardy an ay from the lower end of the stem 16 as theco, senergized and de-energized respectively. `The bore 85 is dened by aligned central or axial enings in discs 86, 81 and 88 of insulatingnia al` which are also employed as the means for in ,l ting and'mounting the contact pieces to be `engaged by the movable ball or armature member jof the relay.

The relay is provided with a plurality of normally' open contacts 89a, 89h and 89o, each of these contacts being vconstructed as sector shaped portion of thin suitable metal, the contacts 89a and 89h being identical in construction, and each of them provided vwith a tail piece or connection terminal 90 by which'electricalconductors may be connected to therespective contact members. The contact member 89e is likewise provided with a terminal lug or extension 9i by which electrical connection may beymade thereto.

The intermediate insulation disc 81 is provided upon its upper face with a series of sector shaped depressions 92 extending therein to a depth sub- 89c are formed, .f'so that the contact members when seated in the depression will have ytheir upper surfaces flush with the upper face of the disc 81.

Referring now to Fig. 11, the contact members 89a, 89h and 89e assembled upon he disc 81 and inserted into the shell 82 will be rigidly held in place by abutment with the thin upper insulation disc 81.

The apices of the contact members 88a, 89h and 89o project inwardly to some extent within the cylindrical bore 85 within which the contact ball moves so that whenever the coil 11 is energized the ball 84 will be drawn upwardly toward the stem 16 and will engage the extending apices of the contact members 89a, 89h and 89e, thereby completing the electric circuit between all three 0 of these contact members. .By reason of the use of three of such-contact members it will be apparent that the ball will make three point contact with these Contact members and will positively engage and bridge between contact members 89e and 89a and contact members Sila-89h and contact members 89e and 89h, thus insuring complete electrical onnection between all of the contacts.

ofthe disc 81 is similarly provided With se'ctcrshaped depressions which are `adapted to receii/,eiandl hold therein a duplicate set of contact members 89d, 89e and 89j, the apices of which'p'roject inwardly of the bore 85 to such extent thatwhenever the relay coil 11 is deenergized the b ill drop upon and lnter-en gage all three of the contact members, thus providing "normally closed contact members to be utilized in the circuit 'hereinafter described.. Again, as was described with reference to the contact members 89a, 89h and 89o, the lower or dupli cate set of contact members are held inplace within the recesses by a lower insulation disc`99= "L,

set within and frictionally or otherwisev secured. withinvthe open end of the shell 92. Asishownin Fig. 11, projecting terminal ends 90 and 9| jjof Y the contact members are accessible ythrough suit able slots 94 and 95 in the. shell 82'so that'ready connection of conductors may be made therewith In order that the circuit of the device'llnay ree"- main open while drilling is in progress vand bel' closed upon interruption of the. operation to initiate the signalling current we employ he agitation" switch shown in lligs.f"-9fa ndf The selected form of agitation-'swim v bration responsive switch disclosedjhe com# prises an elongated, tubular body memberpreerably having an external diameter approximate-f after described, we prefer to lline the bore 91fwith A a tubular section of insulation material 98. The lined bore 91 defines a vertical cylinder in which is mounted a ball iioat99,` preferably constructed of steel or similar metak j 1 y Located at the lower end of the bore 91 are a pair of electrical terminals, or contact members and IOI, which may vcomprisey enlarged heads on slender bolts |02 extending from thevbore91 to the lower end of the body member 96, suitable in-l sulation as indicated at |09 being interposed between the contact members |90 and |0I and the metal of the body member, while the bottom of the bore 91 may be formed Aby adisc or insulation material |04 having a centrally disposed opening |05 therein.

The bore 91 may be disposed eccentrically in the body 96t0 permit the second bore or br-Pass bore |06 to be disposed within the body member. The by-pass bore |06 has a lateral portion |01 thereof, extending laterally of the body member to intersect the longitudinal axis of the bore 91. Extending from the lateral portion |01 of the bypass bore and intocommunication with the main bore 91 is a valve passage |08 which includes a seat |09 for a ball check valve H0. The upper end of the main bore 91 and the upper end of the by-pass bore |06 terminate somewhat short of a plug or cap employed to seal the upper end of body 96.

Thus, by iilling the bore 91 and the by-pass bore |06 with oil or similar relatively heavy fluid,

. as so that-iii' ,megeventgthe' tact members |00 and |0|. The diameter selected for the ball 99 relative tothe diameter of the free "1531191.11 #hat a small jposiuonofzrestfo appreciableiengtiroltirrie i' suiiicie'nt--inlantityf of fthe *liquidy below the ballj '9 `willleak'past'and lper vt the ball 99 'to desee intolelectrical contact'engagement with the corp-'3` |00and1|0|.f-'While, by proper selection'uofpf Y. "ther, ameterof thefball and the bore 91.1 will :ace "l complish this 'result' -Within relatively friarroivfA4 Q. limits. we.fprefer toprovide an adjustable' lealr.-v

taeter.

age control lby which the-time .required .for the lS.'uclifailli-"ishftnieri-t. device lsfreadily lcomprised of a smallleakageibore 2 intersecting both `the main g -fbore 1911and thabyp-nass bore il 06,.'ak suitable setl,20; screw-or'needlevalve ||3 being threaded ito the leakage .boe- ||2 bywliich'the effective area of the bore` for leakage of iluid from vthe lower end of the bore 91 .may be carefully and accurately I regulated. As will be obvious, the foregoing construction is extremely rugged and capable of withstanding considerable shocks and abuse and is particularly ,capable of'withstanding any violent Y vibrations or agitations which might be produced at the drilling tool during its normal drilling operations.

- While one such agitation responsive switch 24 'is employed to start the measuring and transmission operations, a second such switch 24a may be employed for disconnecting the instru.u

ment should the drilling operations be interrupt-r ed or paused for longer than the length of time necessary to make the angle measurement and to transmit them to the ground surface. We prefer, for the purpose of insuring that the indications will be received and properly translated at the ground surface to permit the sequencing relays 23 and the, angle measuring devices to .operate through morev than one'complete cycle any shaking or agitation or vibration of the body member 96 will cause an upward and downward movement of the ball 99. The upward movement of the ball 99 will tend to draw a portion of the liquid into the bore 91 below the ball 99, while such liquid which has been so drawn into the bore 91 will be prevented from escaping from below the ball 99 by a check valve ||0.

Thus, during all vibrationor agitation of the body 96 and the ball 99 and the check valve ||0 will act as a small mechanical liquid'pump tending to lift the ball 99 upwardly within the bore 91 and to hold the ball 99 separated from `the conjnecessary to bring into action all of the angle The switch 24a maybe identical in its construction to the switch 24,` hereinbefore described with reference to Figs. 9 and-l0, the only diilerence required between these switches is a suitable adjustment of the adjusting screw H3 to prolong the time` period between the cessation of vibration or agitation of the switch and the iinal closing of its contacts |00, |0| bythe ball We have illustrated in Fig. 8 a novel electric circuit arrangement which is particularly adapted for use with the various switches, relays and angle measuring devices hereinbefore described. This system is simple and straightforward and operates to'insu're that a monitor signal will be produced at the ground surface to determine whether or not the instrumentalities are in operative condition at the time the measurement is desired, irrespective of the angular inclination of the Well bore.

The circuit also provides for connecting each of the angle measuring devices in sequence to the signalling device so that the signalling device will be actuated a number of times corresponding to the number of angle measuring devices having their contacts closed by displacement of the rolling ball from its normal or central position.

The source of electric current which is il1ustrated in Fig. 8 as being employed to energize the various electrical circuits preferably comprises the battery 25. The wires from the battery and...

the wires comprising the interconnectingV cir- Q cuits between the various relays, switches and theY like may be run through suitablewiring channels or conduits provided within thehousing |5.

Reference to Fig. 5 will indicate that the lnterior housing 32 which is employed to enclose the coil 33 of the signalling device may bereadily Thus current will be supplied to ground. The groundfj'indicated at H9 may be extended 4throughout the remainder of the circuit as a condu'cton if desired, but in order to facilitate manufacture andassembling of the various devices in the housing'l, we prefer that conductor extended down throughout substantiallytlie entire length of the instrument housing `|'5 and may be provided with suitable 'slots or openings therein through which the various electrical conductors may be passed to permit their connection to the various switches and relays assembled within the inner housing 32. 32 is preferably spaced somewhat inwardly of the The inner housing.

interior of the housing l5 to provide an annular space in which the various electrical conductors may be run. If desired, however, a relatively long slot may be provided in the inner housing 32 for the accommodation of wiring and in such.

event the inner housing 32 may have a'diameter sufcient to snugly t the interior of the main housing I5.

In Fig. 8 the conventional electrical symbols have been employed. It will be noted therein that a part of the relays are indicated by the conventional symbolfor an instantaneous relay, whereas. the remainder of the relays are indicated by the conventional symbol employed for indicating The instantaneous relays# a retarded relay. represented on Fig. 8 comprise relays 23 which are lnot provided with the copper collar 8| previously described as comprising a time delay de vice, whereas, those indicated as retarded relays comprise relays 23 equipped with the shading coil or copper'collar 8|.

in the circuit illustrated in Fig. 8 we have selected for each.: of vthe angle measuringdevices to be employed in any one instrument desired a pair of relays. 'In the diagram we have illustrated the circuit arrangement for four angle measuring devices I6. We have numbered the selected angle measuring devices as A, B, C and D to be connected to the signalling device in sequence in the order named. The relays associated with the angle measuringdevice A are designated by the reference characters AI and A2, whereas, those associated with the angle measuring devices B, C and D are likewise designated by the reference characters BI, B2; CI, C2; and DI, D2. The previously referred to monitor signal is produced at the beginning of each cycle of angle measuring operations by monitor relays designated by the referencecharacters Ml and M2.

A more ready understanding of circuit con` nections and the operation o'i the various relays and devices illustrated herein may be had with reference to an assumed set of operative conditions. Assuming that the instrument has been located as herenbefore described upon a drill string which is then drilling a. portion of a well bore at some distance below the ground surface, a short pause in the actual rotation of the drill string and drill bit will permit the vibration re- I84 be grounded to2 some metallic part of the housing l5 as indicated at' ||9 and that the other `portions of the circuit which are to be connected to the conductor H8 be also connected to the metallic parts of the housing, such other connections being also indicated in Fig. 8 by the conventional ground symbol `and-identified by reference character H9. The grounding of conductor I6 by the closing of the agitation switch 24 establishes i a circuit extending from ground by way of Aconductor |20 through normally closed contacts HX on va circuiteholding relay H,y and thence by way vof conductor |2| .through the coil of a sequencey starting relay S and conductor |22 through cony thereon will close after the lapse of such time ductor H4 and thence' back to the battery or source of'cu'rrent 25.

The sequence-starting relay S when energized completes a sequence-starting circuit which ex` tends from ground through conductor |23, the normally open contacts lSa of relay S, thence by -way of conductors |24 andg|26, thefcoi1.of monitor relay Ml, conductor: |21, normally closed con- ,tacts 4Bla,` on relay Bl (associated with angle measuring device IB) thence by way'of conductors |28 and l |4. t"o the battery 25. Relay MI will therefore be nergizedfand Vwill start y.to close its vcontacts-M|a!128,161MIband which, by reason of the time delay interposed by the copper collar delay period. Y

.The closing of 'contacts Mlb will complete a circuit 'for the energization of the coil relay M2 which extends from ground, either through conductors |23, |24 and |25 to the contacts MIb of,

l relay M or, in view of the fact that at the same time the contacts Mib are closed, the contacts M|a will also be closed and hence provides an auxiliary `circuit which extends *from ground by way oi conductors |29, contact M|a oi relay M I, conductor |30, the contacts MIb of relay MI, conductor |32, conductor |33, the coil of relay M2, conductor |34, normally closed contacts D23: (which at this time will be closed) conductor |35, contacts Aly (which also at this time will be closed) and conductors |36- and I4 to the battery V coil, but due tothe employment of the copper collar thereon, the contacts of the relay will be slightly delayed in their closing. However, upon the closing of the contacts M2a of relay M2, a

circuit will be completed for energizing the signailing or sounding device 22 to produce the monitor signal or indication. This circuit extends from ground through conductor |31 and contacts M2a, conductor |38 to one terminal of the coil of signalling device 22, from the opposite terminal of which the circuit extends yby. way of conductor I l4 to the battery 25. A

It will also be noted that upon thel closing oi' contacts Mla and Mib a circuit is established to the coil of relay Ml which renders this relayself-holding, such circuitextendingas hereinbefore traced through ground and conductors |29, contacts Mla, and. conductorsl25 and |26 to the coil of relay Mland thence back to the line as hereinbefore traced. Thus relay Ml will remain energized and hold Vits contacts closed until such circuit isv opened at contacts Bla', which will be' actuated only after relay Bl has been energized inthe sequence.

Also, it will be noted that the closing of con-` tacts Mla and Mlbwill complete acircuit en. ergizing the coil o! relay AI, which is the next relayfin thesequence. This circuit extends, as hereinbefore described, from ground llllrthrough conductors |29, v|30 and |32 Ato the conductors.,

|39 and |40, the coil of relay Al, conductor I4l, the normally closed contacts Cla: (which are closed at this time) and conductors |42 and ||4 to the battery 25. Relay Al will close its contacts tacts M2a: (which at this time are open by virtue of the energization of relay M2) thence by way of conductor |46, the contacts Bly, which at this time will be closed, thence by wayV of conductors |41 and II4to thebattery. l v- A, f

It will'be understoodfron'i thevforegoing description that while relays MI and M2 have been energizedto produce a monitorsignal, the second operation of the signalling -device 22 is prevented by reason of the fact that it cannot operate until after relay M2 has been deenergized.V I'hus, a sulciently long period of time isprovided to insure the production of the monitor beat before any other subsequent. signal can be produced.

When relay Al was energized, and at the expiration of the time delay interposed thereon, closed its'contacts Ala and Alb, its normally closed contacts Aly were opened de-energizing relay M2. The deenergization of relay M2 opens its previously closed contacts M2a cle-energizing the signalling device 22 while at the same time the normally closed contacts M21; of relay M2 will close completing the circuit for energizing relay A2 Vas previously described. It will be noted at this point that upon the completion of the circuit to relay A2,.it, by virtue of the time delay interposed thereon, will not close its contacts for an appreciable length of time after relay M2 has been, and after it has thereby de-energized, the signalling device 22. However, at the `end of this lapse of time imposed upon relay A2 its contact A2a will close, supplying current to the contact ring 2| of the angle measuring device A,

Thus, if at this'time the well bore is deviating from the vertical by an angl in excess of that.

for which the angle-measuring device Als selected, its bau lewin 'lie in geritactvuth the measuring device A (while for Aconvenience lin tracing. the circuit the connection of the base l1 t04 ground All8 is shown as extending as a vconductor, it will be apparent from an inspection `of vFig. 2 that the base l1 is grounded directly to the case or housing I5). The circuit then extends by way of the ball Contact I9, contact ring 2| of angle-measuring device A, thence through` ,It will also be observed that the closing of the I contacts Ala and Alb also prepares and completes a circuit to the next relay in the sequence Bl by Way of the circuit previously traced for relay A2 to conductor |43, thence by way of conductor |50 and conductor I5| tothe coil of relay Bl, and thence by way of conductor |52, normally closed contacts Dls: (which are' closed at this .time),thence by way of conductor l5 and conductor l I4 to the battery.- f f Relay Bl will thereafter close its contacts Bla and Blb as shown when the time has elapsed which has been imposed upon this; relay as its time delay, the contacts Bla completing a holding circuit for the relay Bl in the same .manner as was described with reference to the holding circuit for relays Ml and Al.

It will be noted that relay Ml has up to this time maintained its energized condition, but immediately upon the actuation of relay'Bll this relay will open its normally closed contacts Bla: (in the circuit for relay Ml) and the relay Ml Will at this time be de-energized. Relay Bl when energized will also open its contacts Bly which Awill de-energize relay A2. However, relay A2,

' will, by reason of the time delay4 interposed upon it, open its contacts slowly, opening thev previously energized sounding device circuit through angle-measuring device A after the elapse of a predetermined length of time, and thus de-energizing the signalling device 22, preparing it for a subsequent energization, provided, the anglemeasuring devices further along in the sequence have been so tilted by angularity of the well bore as to hold their balls or contact members intocircuit closing position.

RelayBl having closed its contacts Bla and Blb prepares a circuit for energizing relay B2, which circuit extends from 4ground through-contacts Bla, conductor |54, the c ontacts Blb, conductors and |56 to the coil of relay B2, whence the circuit extends through the normally closed contacts A23: of relay A2v (which-at this time are in open circuit condition), thence through normally closed ,contacts Cl-y of relay CI (which at this time will be closed) and thence by way `of conductor I I4 to battery 25. However, at this point, it will be noted-.that at approximately the same time that the relay contacts Blb are closed, the'relay contacts Bly have de-.enerl vgized relay A2 so that upon the lapse of the predetermined length of'time imposed upon relay A2 the contacts A20: will close and relay B2 will be energized. Relay B2when energized will after a time delay close its contacts B2a, preparing the circuit for angle-measuring device B which will be immediately completed provided the ball con-v tact for angle-measuring device B has been shittedtoits abnormalposition by reason of thedeviation of the well bore from vertical.

`Assuming' that the well bore has deviated from the vertical only by such angle as will actuate angle measuring device A but will not actuate angle measuring device B, the signalling device 22 will not be operated in response to energize.- tion of relay B2, hence the result of the operations thus far described will be that the signailing device 22 will have been actuated twice and will have produced two spaced groups of vibrations which will be received at the ground surface as two spaced sets of vibrations or signals followed by a pause of greater length of time than the normal pause between adjacent beats or signals. To continue the operation, however, of the sequence relays which will continue to sequentially connect angle measuring devices C and D in circuit with the signalling device 22, relay BI, when. it has been energized. will complete a circuit for relay B3. Relay B3 is employed solely for the purpose of removing the starting relay S from the line, so that thereafter the sequence of connection of the angle measuring devices B. C and D and the production of the monitor signal will be continuously repeated in a repeated series of time cycles. The circuit for relays B3 extends through conductor |55 in the same manner as was described with reference to the relav B2, the relay B3 having its coil connected between conductors |55 and iid in shunt l circuit relation to the relav B2.

Relay B3. when energized, will instantly close its contacts B3a which are in circuit with the sequence holding relay H. Thus. seouence holding relay H will be energized through contacts B3n of relay B3, conductor |58, conductor |59, coil of relay H and conductors-|68 and |I4 to the battery 25. Relay H, when energized. closes the self holding contacts Ha which completes a self-holding circuit for this relay by way of conductors |20 and |59.

The energization of sequence holding relay H opens its normally closed contacts Hx. which as hereinbefore described. are in circuit with the starting relay S. thereby de-energizing starting relay S and causing it to open its normally opened contacts Sa and permitting it to close its normally closed contacts S'c.

The normally closed contacts SX are interposed in a conductor |63, which inter-connects the relays associated with the last angle measuring device in the system with the energizing circuits for the rst set of relays in the sequence. namely, the monitor relays MI and M2. so that once the sequence of relays has been started by the sequence-starting relay S and the sequence has been carried through one complete set of operations for connecting the entire set of angle measuring devices successively and consecutively with the signalling device 22, the sequence will be repeated continuously until the main energizing circuits are opened by the second of the agitation responsive switches 24a, which, as will be recalled, will close its contacts at a relatively Vlong predetermined time after the drill string has been brought to rest either for the purpose of making the angle measurement or for any other purpose. y

Continuing the operation, the description of the diagrammatic arrangement shown in Fig. 8 the next relay in the sequence is relay C| associated with angle measuring device C. The relay CI will be energized as soon as the contacts BIb on relay BI have closed, the circuits for the relay CI, eX- tending by way of ground through contacts BIa and Bib of relay BI and thence by way of conductors |55 and |64, the coil of relay CI, conductor |65, normally closed contacts MIx (which will now bel closed since relay MI is cie-energized) and conductors |66 and II4 to the battery 25. Relay CI, when energized, closes its contacts Cla and CIb after the lapse of whatever time delay is interposed upon relay CI, the contacts Cla s closing a self-holding circuit for the relay CI in the same manner as hereinbefore described for relays MI, Al and BI, while the contacts CIb will prepare a circuit for, the energization of relay C2, associated also with the angle measuring device C, which circuit, however, will not be closed until after cle-energization of the relay B2 which had connected the angle measuring device B with the signalling device 22. Upon the deenergization of relay B2, however, the circuit for relay C2 will be completed, this circuit extending through the contacts CIb of relay CI, as hereinbefore described, and thence by way of conductor |61, the coil of relay C2 and thence through normally closed contacts B233 of relayBZ, normally closed contacts Dly of relay DI, and thence by way of conductor II4 to the battery 25.

Relay CI, when energized, will open its contacts Cly de-energizing relay B2 which will alter the lapse of the time delay imposed upon relay B2 open its contacts B241 disconnecting the signalling device 22 from possible energization by angle measuring device B. At the same time relay C2 will be energized and upon the lapse of the predetermined time imposed upon relay C2, this relay will close its contacts C2a, coupling angle measuring device C with the signalling device 22 so that should the ball contact of this angle measuring device C be in circuit closed position the signalling device 22 will be actuated for a fourth time in the sequence. However, we have assumed that the angle of deviation at the time of making the measurement was not sulicient to place the ball contact of angle measuring device C in circuit closing position and hence no further signal will be given by signalling device 22.

Relay CI when it was energized and closed its contacts Cla and CIb, also completed the circuit for energizing relay D|, which circuit extends through the contacts Cla and CIb as hereinbefore traced, and thence by way of conductors |68 and |69, through the coil of relay DI and thence by way of conductor |"I0, normally closed contacts Ala2 ofl relay AI and thence back to the battery 25 by way of conductor I I4.

Relay DI, which is associated with the last of the angle measuring devices D, operates in the same manner as was described with reference to relays MI, AI, BI and CI, and Iafter the lapse of the time imposed upon this relay will close its contacts DIa and DIb andV at the same time open its contact DIy de-energizing relay C2 and DI de-energizes BI in the same manner as the preceding relay in the sequence. The contacts DIa will complete the self-holding circuit for the relay DI while the contacts DIb will prepare a circuit for energization'of relay D2, which is also associated with the angle measuring device D. 'Ihe circuit for relay D2 extends through ,the contactsDla and DIb, and thence by way of conductor I'II through the coil of relay D2 and thence through normally closed contacts C2 of relay C2 and normally closed contacts MIy vof relay MI, and thence to the battery 25 by way of conductor I I4.

As hereinbefore stated, energization of relay DI opens its normally closed contact DIy, dcenergizing relay C2, so that upon the lapse of the time imposed upon relay C2 this relay will open its contacts C2a disconnecting the signalling device 22 from possible voperation by the angle measuring device C and at the same time completing the energizing circuit for the relay D2.

Now upon the lapse of the time imposed upon relay D2 this relay will close its contact D2a and connect the signalling device 22 in circuit with the angle measuring device D, so that should this angle measuring device have its ball contact in circuit closed position the signalling device will be operated for the fifth time in the cycle. However, as stated before, we have assumed that the angle of deviation is such that only angle measuring device A will be in circuit closed position, and hence, even though each of the angle measuring devices is consecutively connected with the signalling device, the signalling device will be operated only twice in each completed cycle, namely, once by the monitor relay and once by angle measuring device A.

At this .point it .might be well to review the effect of the foregoing operations upon the signal receiving and recording apparatus. As stated, during the complete time cycle required for the sequential energization of all of the relays MI to D2, the signalling receiving apparatus or the recording device will be operated twice at the beginning of the cycle and thereafter will not be operated during the remainder of the cycle.

As will be apparent to those yskilled in this art, it is possible that either through inattention or some other reason thedrller or person who should receive the information at the ground surface may have failed to observe the complete set of signals transmitted thereto, and hence we prefer to so arrange our device and our system that the same set of measurements, the same set of signals will be produced at least a second time,

lthat is a second cycle of operations will be performed repeating the information obtained and transmitted during the initial operation hereinbefore set forth. The manner in which we have accomplished this repetition of the operations lies in inter-connecting the relay DI with the monitor relay MI, that is we interconnect the relay for the last of the angle measuring devices with the monitor relay so that after the last angle measuring device has been connected in the circuit it will start the entire sequence all over again by starting the operation of the monitor relay MI.

Referring to Fig. 8 it will be observed that when relay DI closed its contacts Dla and Dlb, it completed the circuit for the energization of relay M| which is independent of the initial circuit required for the energization of relay Ml. This circuit extends by way of the contacts D|a and Dlb on relay DI and thence by way of conductor |63 through normally closed contact Sa: of the sequence starting relay S (which at this time it will be recalled is de-energized) land thence the circuit continues by way of conductors |12, |24 and |26 to the coil of relay M| and thence back to the battery 25 as previously traced for repeat the cycle of operations for more than say three or four times, we conserve the energy of the battery 25 by disconnecting the relays as a result of the operation of the second agitation switch 24a. When agitation switch 24a closes its contacts the circuit will be completed for a line disconnecting relay L, which circuit extends from the battery or source of current 25 through conductor ||5, the contacts of agitation switch 24, conductor ||6 and thence by way of conductor |13, the contacts of agitation responsive switch 24a, conductor |14, the coil of line disconnecting relay L and conductors |15 and ||4 to battery 25. The line disconnecting relay L when energized will open its contacts La: and open the circuit between the battery 25 and ground and all of the relays contained within the circuit beyond contact Lm will be disconnected and will remain disconnected until the drill string is again operated and a further set of measurement is desired.

An inspection of the wiring arrangement shown in Fig. 8 will demonstrate that the circuit employed within is an extremely simple circuit to connect up and that it is peculiarly adapted, by reason of the connections of the contacts of the several relays, to employ the particular character of relay hereinbefore described. v

It will be apparent, therefore, that we have provided an extremely simple device which may be permanently located on the drill string and hence is instantly available to the driller for making angle measurements repeatedly throughout the drilling operation, and which does not require the disconnection of any portion of the drill string for the purpose of making the test.

the relay MI. Relay MI, when re-energized will Y We have also provided a system of sound transmission or signal transmission from an instrument which may be located at any distance below the ground surface, in which we utilize the efficient transmission qualities of the column of liquid which is always present in and during the drilling operations, and we are thereby enabled to avoid any conductors or any other transmission devices extending from the ground surface to the bottom of the hole,

We have also provided an instrument which has each of its elements so designed as to be extremely rugged, almost impossible to break, injure or destroy, particularly the various switches and relays which are employed. The agitation responsive switch, for example, is made of only two moving parts, namely, the relatively heavy rugged ball float and the simple ball-check valve which, as is well known, can withstand the abuses to which it may be subjected during the drilling operations.

The same principle of relatively few moving parts and each of those parts being made in the form of metal ball is likewise employed in the construction of each of the sequence 'relays so that there are no delicate instrumentalities requiring careful adjustment or careful handling or even careful machining and manufacture.

We have also shown a simple but effective means for producing signals of predetermined frequency and means for receiving such signals. which in themselves act as a filter to filter out and prevent interference between the signals desired to be transmitted and other extraneous noises which may be present either at the bottom of the hole or at the vground surface.

Also We have described an extremely simple and effective manner in which the instrument may be mounted within the drill string, so as to utilize the greatest possible effect of transmission of the signals to the mud stream or fiuid column and yet avoid any appreciable injury to the device or to its mounting apparatus by reason of the fact that such circulating mud fluids are usually highly abrasive. Further, it will be recalled that the mounting of the device within the drill string is located out of the path of core bits, or other instrumentalities which may be employed during the drilling of the well to pass down through the circulation openings or passages.

While we have shown and described the preferred embodiment of our invention, we do not desire to be limited to any of the details hereinbefore illustrated and described, except as defined in the appended claims.

We claim:

1. In a system for measuring conditions existing in 'a' well bore having extending thereinto from above the ground surface a tubular rotary drill string which contains a column of liquid extending to a point above the ground surface, said drill string including also' al stationary portion disposed above the ground surface. a device secured to the lower end of said drill string for through with#awcross-sectional area in excess"y of the cross sectional area of the normal fluid' 1 j opening throughsai-d drill string, whereby the thereby minimize measuring a condition in said well bore and inf cluding a signal producing means including aI diaphragm means exposed to said column of liquid at the location of said device, means for vibrating the diaphragm at a predetermined frequency upon actuation of said signalling device for creating a series of pressure waves in said liquid column, means above the ground surface secured to said stationary portion of said drill string and exposed to the effect of the pressure waves created bv said signal producing means for receiving said waves, and means for rendering said signal receiving means responsive only Y to pressure waves of predetermined frequencv.

2. In combination with a device insertable into a well bore containing a liquid column extending to .the ground surface, a signal producing means associated with said device and including a diaphragm located on said measuring device and exposed to the liquid column at the location of said device within said bore, said signal producing means including a weight suspended from said diaphragm bymeans of a resilient rod. the mass of said weight and the dimensions of said rod being selected to vibrate said diaphragm at a predetermined frequency, and signal receiving means at the ground surface tuned to receive signals or vibrations only of said predetermined frequency.

3. In a system for measuring conditions existing in a well bore which contains a drill string "and a column of liquid circulating therethrough,

a device for measuring a condition existing in said well bore, means mounting said device in said drill string adjacent the lower end of said string and including a tubular mounting member having an interior bore extending therethrough with a cross-sectional area in excess of the cross sectional area of the normal fiuid openvelocity ofthe fluid through said mounting member is less thanlthe velocity thereof through other parts Mof said string, and the abrasive action of saidklflu @on said measuring device is ,and means for securing said measuring device"in off-set relation relative to the longitudinalig'axis of said drill string and counterweightmyefa'ns yon said drill string to compensate for th balancing of the drill string by and a column ofiliquid circulating therethrough, y

a device for measuring a condition `existing in said well bore,. rne`ans mounting said device in said drill String adjacent the `lower end of said string and includ-ing a tubular mounting member having an'" -terior bore extending therethrough with @cross-sectional area in excess of the cross sectional area of the normal fluid opening through said `drill string, whereby the velocity of the uidthrough said mounting memb er is less thanthe velocity thereof through other parts fof said string, and the abrasive action ofsaid fluid on said measuring device is thereby minimized, and means for securing said measuring device in off-set relation to the longitudinal axis of said drill string, said measuring device including a plurality of batteries and 'counter-balancing means disposed in diametrically opposed offset relation with respect to the longitudinal axis of said drill string, said counter-balancing means including storage means for a supply of battery cells for the operation of said measuring device. y

6. In a syste'rn for measuring conditions existing in a well bore which contains a conduit through which liquid is pumped into said well bore, said conduit having therein a column of liquid extending to a point above the ground surface, the combination of a signal producing device located in the Well at some distance below the ground surface for producing pressure wave impulses in said column of liquid, a receiving device secured to said conduit above the ground surface for receiving said pressure wave impulses including a diaphragm exposed to the liquid in sald conduit, and means rendering said diaphragm responsive particularly to pressure wave impulses of predetermined frequency.

ing through said drill string, whereby the ve- 7. In a systenrgfor measuring conditions existing in a wel] bore'fla device insertable in said well bore for measuring conditions existing therein, means for repeatedly transmitting said measurements fromgsaiddevice to be received and transin the well bore and for` completing said circuit only when said device is/brought to a condition of rest, and additional means for opening said circuita predetermined time after said device has been brought to rest andsubsequent to the completion `of the circuit by said first named means.

8. In a system for measuring conditionsrexisting .in a well bore, a device insertable in said well bore for measuring conditions existing therein including electric switch means closable in 'response to the existence of acondition to be measured, means for transmitting said measurements from said device to be received and translated at the lground surface, said transmitting means including a source of electric current located on said measuring device connected in an electric circuit with said switch means, means for conserving the life of said source of electric current including means for opening said electric circuit Whenever said device is moved in the Well ,bore and for completing said circuit only when said device is brought to a condition 'of rest, and additional means independent of` said switch means for opening said circuit apredetermined time after said device has been brought to rest and subsequent to the completion of the circuit by said rstnamed means.

' 9. In asystem for measuring conditions existing in a well bore, a device insertable in said Well bore for measuring conditions existing therein, signalling means on said device operative to repeatedly transmit to the ground surface signals' corresponding to 4the condition'measured vby said device, means for rendering said device operative to effectively measure said condition` only when said device has been brought to rest in said well bore, and means for rendering said device inoperative to measure said condition after the lapse of a predetermined length of time after said device has been brought to rest.

' l0.' In a system for measuring conditions existing in a Well bore, av device insertable in said Well bore including an electric switch means closable in response to the existence of a condition to be measured; an electrical signal producing means connected in a main partial circuit With'a source of electric energy; a plurality of time delay relays connected in a chain circuit with each other and with said source, said chain circuit being so arranged that said relays are alternately energized and de-energized in a timed succession; and a pair i of a well bore, a device insertable in said well bore including a plurality of electric switch means each closable by inclination of said device from the vertical by a different amount; a source of electric energy; a plurality of time delay relays connected in a chain circuit with each other and with said source, said chain circuit being so arranged that said relays are alternately energized and de-energized in a timed succession; an electrical signal producing means connected in a main partial circuit with said source; and a plurality of branch circuits connected to complete said mainpartial circuit, each of said branch circuits including in series a different one of said electrical switch means and a contact of a different one of said time delay relays.

:'12.r In a system for measuring the inclination of a Well bore, a device insertable in said well bore including a plurality of electric switch means each closable by inclination of said device from the vertical by a different amount; a source of electric energy; a plurali-ty of time delay relays connected in a chain circuit with each other andvwith said source, said chain circuit being so arranged that said relays are alternately-energized and deenergized in a timed succession; a starting switch closable to energize the first of said relays in said chain circuit, the last relay in said chain circuit being connected to re-.energize said first relay; an electrical signal producing means connected in a main partial circuit with said source; a plurality of branch circuits connected to complete said main partial circuit, each of said branch circuits including in series a different one of said electrical switch means and a contact of a dilerent one of said time delay relays; and cut off means for disconnecting said source a predetermined time after closing of said starting switch.

GEORGE E. LEWIS.

RICHARD H. DUVAL. BRUCE H. RULE. RAY M. crrENoWE'rH. 

